Pro Umatic and VHS haul.

[Dave A]

My guess is the tape fell off the tape path somewhere and is drooping out of view of any tape sensor lamp. You may have lost a rewind belt if JVC uses it and the tape has lost tension in the guides. The belt is under the bottom cover on a Sony. The deck is confused.

You may have to lift the lid and finger-wind the loading arms back in to the shell. This is easy on a Sony...not sure about JVC but it may be similar.

On a Sony you will see a white plastic worm gear arrangement to the left of the loading ring. It's tight but you can reach a finger in there and rotate the gear. Pick the direction that starts moving all the threading arms back to the casette. Carefully lift up any fallen tape and guide it up in to the air while turning. The tape will not retreat back to the casette. You are just clearing the loading assembly. You will feel the arms stop when they reach the end.

Now you can try to eject but while you do, hold the casette door open with a finger and keep the tape loop up in the air away from harm. You may have to power up and hold the eject button to fool the deck to get it to eject. If the JVC is a manual eject proceed on. You will probably wrinkle a piece of tape no matter how hard you try though if it is not already wrinkled. If the casette pops up now carefully slide it out holding the tape loop. From here, hold the door open and finger wind the tape back in to the casette and let the door close. If the door does close, there is a slide release for the door on one side of the casette door. Use a pen and push the lever down to release the door.

All of that said, that is the Sony fix. JVC is probably similar as U-Matic was a standardized design like VHS. I lost track of how many times I did this.